Wasilewska L D, Bralczyk J, Mazurkiewicz J
Acta Biochim Pol. 1984;31(1):91-102.
Characteristics of the total DNA preparations isolated from apical parts of dwarf pea seedlings untreated and treated with gibberellic acid (GA3) were compared. Analytical centrifugation in a self-generated CsCl density gradient revealed the occurrence of a heavy satellite DNA band (p = 1.712 g X cm-3) in addition to the main DNA band (p = 1.696 g X cm-3) in the DNA preparation extracted from GA3-treated seedlings, that could not be detected in the DNA isolated from untreated plants. The existence of this GC-rich DNA fraction was additionally confirmed by means of derivative DNA melting profiles. Comparison of the reassociation kinetics obtained for control DNA with DNA from GA3-treated plants showed changes in the percentage distribution of three main DNA sequence classes, with different repetition frequency in the haploid pea genome. It is postulated that such a variation in the percentage of different C0t families might reflect the selective DNA replication evoked by hormonal treatment of dwarf pea plants.
对从未经处理和用赤霉素（GA3）处理的矮生豌豆幼苗顶端部分分离得到的总DNA制剂的特性进行了比较。在自生CsCl密度梯度中进行分析离心，结果显示，从经GA3处理的幼苗中提取的DNA制剂，除了主DNA带（p = 1.696 g X cm-3）外，还出现了一条重卫星DNA带（p = 1.712 g X cm-3），而从未经处理的植物中分离的DNA中未检测到该带。通过衍生DNA解链曲线进一步证实了这种富含GC的DNA组分的存在。将对照DNA与经GA3处理的植物的DNA的重缔合动力学进行比较，结果显示，单倍体豌豆基因组中具有不同重复频率的三种主要DNA序列类别的百分比分布发生了变化。据推测，不同C0t家族百分比的这种变化可能反映了矮生豌豆植株激素处理引起的选择性DNA复制。
